Added AccountManager.find_account method

Ignore-this: 6c6fd8721dc2f6ed06124647fb1bda73

darcs-hash:20090318132730-1e3d8-0775abd3b2d6405b15ccec259479eb948ebe23ff
Changed default listening port values

Ignore-this: 9fddc7425283bbb655a920047070d3ed

darcs-hash:20090318132735-1e3d8-0a73be9a609159775a620ce4fc528310c82fe369